Field of the Invention
The present invention concerns an acquisition window for a medical apparatus, in particular for a computed tomography apparatus, of the type of an element made of a suitable material (in particular an x-ray-permeable material such as a ring or a strip of such material) and at least one attachment element to attach the element to a medical apparatus (in particular to a computed tomography apparatus). Furthermore, the invention concerns a medical apparatus (in particular a computed tomography apparatus) with such an acquisition window.
Description of the Prior Art
The present invention is explained in the context of the example of a computed tomography apparatus. Computed tomography apparatuses have a housing to protect the electronic components from contaminants (for example the entrance of fluids) and from external mechanical effects. A patient to be examined or object to be examined is typically positioned in a measurement region, which is located between the essential components of the acquisition system of the computed tomography apparatus (thus between the radiation source and the detector), and is moved through this measurement region. Therefore, the housing is typically located between the radiation source and the detector. In order for the image acquisition to not be negatively affected by the housing, the housing typically has an acquisition window in this region, this acquisition window being arranged annularly around the measurement region and through which the radiation is transmitted. This acquisition window is formed as a ring or a material strip closed to form a ring, and is typically also designated as a radiation passage window or seal ring. The acquisition window is thus part of the casing or housing of the computed tomography apparatus and is situated in the region of the rotating fan beam. Such an acquisition window must have various properties. In particular, the acquisition window must be designed such that the x-ray radiation (and possibly laser light used to identify the acquisition plane, or for positioning) are transmitted without the respective radiations being too significantly weakened. The acquisition window thus should not be too thick, such that—among other things—a higher radiation dose is necessary or the image quality is negatively affected by disruptions or artifacts. Moreover, the acquisition window must be formed of a homogeneous, radiation-resistant material and satisfy the legal ordnances with regard to flame resistance and fire safety. The acquisition window must also be able to compensate for tolerances and misalignments between the front and back casing parts. Furthermore, the acquisition window must be resistant to cleaning and disinfectant agents and have contact protection capability during the operation of the medical apparatus, which means that it must be mechanically stable so that it can withstand a defined load (in particular a load coming from the measurement region). Therefore, such an acquisition window normally has at least one material ring made of a material that is permeable and resistant to x-ray and optical radiation. For example, such a ring can be produced from a material strip of a suitable material that has been joined at the ends thereof by ultrasonic welding, so as to form the ring.
In the case of typical seal rings or acquisition windows that are arranged on a medical apparatus but not permanently attached to the apparatus casing, the problem of the seal ring or acquisition window falling off occurs in the installation or deinstallation of the seal ring. The seal ring or the acquisition window falling off can cause damage to the coating of the seal ring (for example, scratching the surface of the seal ring). Moreover, nearby components can also be damaged. This problem can be solved, for example, by applying adhesive tape between the seal ring and the medical apparatus or the casing parts to which the seal ring is attached, but this solution is time-consuming. Moreover, the adhesive tape must be attached and removed again with care in order to avoid damage to the coating of the seal ring. Moreover, multiple pieces of adhesive tap must be applied so that the seal ring does not fall off. Finally, the adhesive tape can release if it has not been properly applied, so damage to the seal ring or the nearby components due to the seal ring falling off in the installation or in the deinstallation cannot be entirely precluded.